I had to clean and re-do the adhesive tape of Acer Aspire 8951G screen as bugs/insects were leaving inside the screen and the plastic on top of the screen stop sticking to the frame. I also had to replace the battery where I had to remove the bottom case and keyboard. When testing the battery, make sure to lock the battery switch (orange) located underneath the case, or else you will see "No battery detected" on Windows, even though your battery has been plugged in to the board.

Panasonic NCR-B/819

If you got "no battery detected" on Windows, then you probably didn't switch the orange lock located underneath the laptop, picture above.